A brief summary of version differences. Of note, Jeremy Soule had an input in every version of (including the Game Boy versions), and is credited in every release. EA also has members of staff supervise every sound design on all platforms.

Nowhere online really documents all the different console versions and their differences, but a short video comparison here covers some of the details below.
https://www.youtube.com/watch?v=TsSfkFS1AdM

- PS1
Completely unique to all the other releases, featuring its own sound design and levels. A large portion of the game are assets from the previous Harry Potter game.

- PS2
The 6th gen versions are almost identical, except the PS2 version was developed by EA UK and so has numerous differences. The biggest being that you can free-roam around the castle in the game, and land your broom anywhere you like. Other differences include sound design differences, different cutscenes, gameplay alterations for a generally easier difficulty.

- GameCube / Xbox
Nearly identical to the PS2 version, except you can't freeroam and the sound design was handled by a different team. Not musically identical.

- PC
An entirely different game than all other versions. Was made by a different developer than the 6th Gen versions.

- GBC
The GBC has different sound and music than the GBA version. They don't share any levels or similarities.

- GBA
Completely different than the GBC version, and the sound design / music was outsourced. Has connectivity with the GamCube to unlock more levels.